Henry Ford is frequently quoted saying that if he had asked people what kind of car they wanted they would have said a faster horse*. Many people use that to criticize user centered design on the basis that people don’t know what they want and therefore can’t be a valuable source of information in product design. This criticism shows a bit of misunderstanding on what user centered design is about.
It’s not about servicing the user by tailoring to their every whim. It is a about servicing the user in a way that makes them more successful while at the same time understanding that the user is not a technical person, not a user interface or interaction designer and many cases only has a limited view of how the product is used.
This is one of the most demanding tasks of User Centered Design. Because it requires from the designer to take a step back and understand what it is that the user means, not what he is saying. Understand what the users needs rather than what it is that they want.
This means discussing what the user wants to achieve rather than what bugs are currently annoying him or what he can’t do with the software he is using now.
An example might be a user complaining that the different systems he is using make it difficult for him to copy/paste dates between them because they use a different date-format. Here the knee-jerk reaction would be to make sure that all the systems he uses have the same date-format. Easy! But that is not the problem here. The real issue is why does the user need to copy/paste information between systems? Why are there so many systems?
It’s the ability to decipher the needs of the user from his wants that differentiates between a usability expert and a user experience designer.
*”The trouble with quotes on the internet is that it’s difficult to discern whether or not they are genuine” Abraham Lincoln